diff --git a/platform/webext/install.rdf b/platform/webext/install.rdf
index 8487254..b0dc177 100644
--- a/platform/webext/install.rdf
+++ b/platform/webext/install.rdf
@@ -20,7 +20,7 @@
             <Description>
                 <em:id>{{ec8030f7-c20a-464f-9b0e-13a3a9e97384}}</em:id>
                 <em:minVersion>53.0a1</em:minVersion>
-                <em:maxVersion>*</em:maxVersion>
+                <em:maxVersion>56.*</em:maxVersion>
             </Description>
         </em:targetApplication>